Guppy Phenomenon

[This Old Spouse]

I had read about this, but never saw it before and frankly, didn't quite believe it happens. But in the past week, the two youngest female fry had are now males, complete with gonopodia and colors on the body. Last week they were females, with gravid spots. Wow.

 

[Fishy friend2]

How did that happen? Are you sure that they were born females and the gravid spot wasn't just marks on the body of the fish, that is so cool that they can do that

 

[This Old Spouse]

Yes. I'm sure.

 

[fish48]

All guppys start out looking like female / your fry have been slowly developing in to males they cannot develop a complete gonopodium in one week

 

[This Old Spouse]

If you say so. I watch these fish very closely, and I'm just reporting what I'm seeing.

 

[lilfishie]

it does take long than a week for the gonopodium to fully form, until then males often appear as females especially if theres males in there as they will be sub dominant

 

[fish48]

If you say so. I watch these fish very closely, and I'm just reporting what I'm seeing.

sorry you don't convince me you need to look at these fish very closely
i don't believe you have studied them closely Enough

 

[Dieses Madchen]

I know platy females have been known to change sex in a single sex environment.....i didn't know that guppies have been known to do that too...

 

[fish48]

Although it may be possible for some livebearers to change sex I believe when or if it occurs it would be on very rare occasions true sex changes in these fishes are not as common as many people beleve it to be. my beliefs are that there are many young and inexperienced fish keepers that often buy fish from there lfs and not fully understanding whether they have bought true males meaning that they often buy juvenile fish that can often take a long time to sex out some may take a year or moor before they fully develop a gonopodium.

All livebearers start of looking like females, many new fish keepers believe that there livebearer as changed sex . what happens when a dominant male dies or if it is removed the next one will take its place and develop it’s true gender.
very old female swordtails can take on the characteristic of a male swordtail however they can not function as a normal male

 

[This Old Spouse]

I've raised guppies for more than a year. These fry are not from my LFS and I study them every day. I've not seen this happen previously with the hundreds of fry that have passed through these tanks. I don't know HOW or WHY it happened, but it did. I'm not a scientist, just very observant.

 

[fluttermoth]

Livebearers can't change sex; they're just late developing males; they do look like females, but if you were to have had them DNA tested, it would have shown that they were males. The so called 'gravid spot' is not an indication of pregnancy (or of 'femaleness').

 

[Paradise3]

I once had a female that was fully grown who dropped one lot of fry then had a sex change...

 

[fish48]

Livebearers have sex and may even change there minds about sex they don't change there sex lol

 

[This Old Spouse]

When a large group of females is kept together with no males, according to all the research I've been seeing on the web, it's possible for livebearer females to become males. I wouldn't expect that it could happen with older females, and it certainly doesn't happen the other way around, but it does happen. I'd imagine it's the way to perpetuate the numbers when all else fails.

 

[fish48]

once a female has been hit by a male then as you know a single female can produce up to 6- 7 broods and drop a brood every 3 0r 4 weeks .a average brood can very from 30 up to 150 or moor there is no need for them to change sex. so if i had a thank with 20-30 female guppy/s basicly you are saying sooner or later one or some will changs sex ?